Vinyl halide polymerization with adipoyl peroxide and hexamethylene diamine



. vinyl chloride was converted to polymer.

Patented Nov. 17, 1953 UNITED STATES ATENT tore VINYL HALIDEPOLYMERIZATION WITH ADIPOYL PEROXIDE AND HEXA- METHYLENE DIAMINE HaroldF. Park, East Longmeadow, Mass., as-

signor to Monsanto Chemical Company, St. Louis, Mo., a corporation ofDelaware No Drawing. Application October 24, 1952,

Serial No. 316,788

Claims.

Another object is to provide a new catalyst for the polymerization ofvinyl halides.

These and other objects are attained by polymerizing oxygen-free vinylhalides in contact with a mixture of adipoyl peroxide and hexamethylenediamine.

The following examples are given in illustration and are not intended aslimitations on the scope of this invention. Where parts are mentioned,they are parts by weight.

EXAMPLE Vinyl chloride containing substantially no oxygen was compressedto 250 atmospheres in the presence of 0.1 part of a mixture of molecularequivalent amounts of adipoyl peroxide and hexamethylene diamine per 100parts of vinyl chloride. The compressed mixture was forced through asteel reaction vessel heated to 300 C. The mix- .ture passed through thereaction zone in about 90 minutes and it was then forced through asuitable pressure-reducing valve into a cool atmospheric pressure zone.

The polymer was hard, transparent and easily molded.

It is essential that the vinyl halide used in the process of thisinvention be substantially oxygenfree. Amounts of oxygen as small as0.06% by weight speedily poison the catalysts of this invention.

In place of the vinyl chloride used in the example, other vinylhalidesor mixtures of one or more vinyl halides withone or more othercopoly- 'acrylic acid, acrylonitrile, acrylic esters including methyl,ethyl, propyl, phenyl, etc. acrylates, acrylamide, alpha-substitutedacrylic acids,

nitriles, esters and amides such as methacrylic acid, methacrylonitrile,ethyl methacrylate, methacrylamide, methyl methacrylate, atroponitrile,

. etc.; the acids, esters and amides of alpha,betaethylenicallyunsaturated dicarboxylic acids such as the fumaric, maleic, citraconic,itaconic, etc. acids, theiresters and amides, etc. If a copolymer isprepared b the process of this invention it should contain more than 50%by weight of vinyl halide.

The reaction conditions which may be used vary from 100 C. to 400 C. andfrom to 500 atmospheres pressure. The particular conditions used incombination with the amount of catalyst determine the molecular weightand, consequently, the hardness and moldability of the polymer produced.In general, it may be said that a combination of 100 C., 500 atmospherespressure and 0.01 part of catalyst will produce the highest molecularweight and the hardest polymer. In fact, such conditions may result in apolymer so high in molecular weight that it is not easily molded underconventional conditions, i. c. it is necessary to substantially raisepressures and temperatures used for molding or extrusion.

Theamount of catalyst mixture used may vary between 0.01 part to 5 partsper 100 parts of monomer or monomer mixture. At the lower part of Morethan of the,

the range, polymerization is slow unless the higher temperature range isused, and the molecular weight of the polymer is relatively high. Atfrom 3 to 5 parts, polymerization is quite rapid even at C. and theproduct is so low in molecular weight that it approaches the lower limitof moldability. In order to obtain the most accurate control of thereaction rate and to produce an optimum range of moldable polymers, theamount of catalyst ispreferably restricted to from 0.01 to 1.0 part per100 parts of monomer or monomer mixture. The amounts of thecomponents inthe catalyst mixture should be equal on a molar equivalent basis.

The adipoyl peroxide, which may also be called adipyl peroxide, has thefollowing formula:

chloride with 0.5 mol of sodium peroxide followed by hydrolysis of theunreacted acyl chlorine atoms. The reaction should be carried out in anaqueous medium at about 0 C. and care should be taken to avoid an excessof sodium peroxide. This invention provides a. simple process forpreparing relatively high molecular weight vinyl halide polymers whichare easily molded and extruded under conventional conditions. It alsomakes it possible to obtain vinyl halide polymers ranging from soft andwaxy to hard and resilient solids.

This application is a continuation-in-part'of co-pendine; applicationSerial No. 128,503 filed November 19, 1949, now abandoned.

It is obvious that many variations may be made in the processes andproducts of this invention Without departing from the spirit and scopethereof as defined in the appended claims.

Whatis claimed is: i

1. A mass polymerization process which comprises polymerization a vinylhalide at from 100 C. to 400" C. and at 25 to 500 atmospheres pressurein contact with a mixture Of molecular equivalent amounts of adipoylperoxide and hexamethylene diamine. r

2. A process as in claim i halide is vinyl chloride. 3. A masspolymerization process which comtvl'iereinl the vinyl 4 prisespolymerizing 100 parts of a vinyl halide at from 100" C. to 400 C. andat 25 to 500 atmospheres pressure in contact with from 0.01 to 5 partsof a mixture of molecular equivalent amounts of adipoyl peroxide andhexamethylene diamine.

4. A mass polymerization process'which comprises polymerizing 100 partsof vinyl halide at from 100 C. to 400 .C. and at 25 to 500 atmospherespressure in contact with from 0.01 to 1.0 part of a mixture of molecularequivalent amounts of adipoyl peroxide and hexamethylene diamine.

5. A mass polymerization process which cornprises polymerizin 100 partsof vinyl chloride at 300 C. and 250 atmospheres pressure in contact with0.1 part of a mixture of molecular equivalent amounts of adipoylperoxide and hexamethylene diamine.

. HAROLD F. PARK.

No references cited.

1. A MASS POLYMERIZATION PROCESS WHICH COMPRISES POLYMERIZATION A VINYL HALIDE AT FROM 100* C. TO 400* C. AND AT 25 TO 500 ATMOSPHERES PRESSURE IN CONTACT WITH A MIXTURE OF MOLECULAR EQUIVALNET AMOUNTS OF ADIPOYL PEROXIDE AND HEXAMETHYLENE DIAMINE. 